Annotation of mandoc/apropos_db.c, Revision 1.32.2.3
1.32.2.3! schwarze 1: /* $Id: apropos_db.c,v 1.32.2.2 2013/10/05 20:30:05 schwarze Exp $ */
1.1 schwarze 2: /*
1.31 kristaps 3: * Copyright (c) 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
1.3 schwarze 4: * Copyright (c) 2011 Ingo Schwarze <schwarze@openbsd.org>
1.1 schwarze 5: *
6: * Permission to use, copy, modify, and distribute this software for any
7: * purpose with or without fee is hereby granted, provided that the above
8: * copyright notice and this permission notice appear in all copies.
9: *
10: * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11: * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12: * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13: * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14: * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15: * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16: * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17: */
1.19 kristaps 18: #ifdef HAVE_CONFIG_H
19: #include "config.h"
20: #endif
21:
1.32 kristaps 22: #include <sys/param.h>
23:
1.1 schwarze 24: #include <assert.h>
25: #include <fcntl.h>
26: #include <regex.h>
27: #include <stdarg.h>
1.6 kristaps 28: #include <stdint.h>
1.1 schwarze 29: #include <stdlib.h>
30: #include <string.h>
1.8 kristaps 31: #include <unistd.h>
1.1 schwarze 32:
1.32.2.3! schwarze 33: #if defined(__APPLE__)
1.19 kristaps 34: # include <libkern/OSByteOrder.h>
1.32.2.3! schwarze 35: #elif defined(__linux__)
! 36: # include <endian.h>
! 37: #elif defined(__sun)
! 38: # include <sys/byteorder.h>
1.1 schwarze 39: #else
1.32.2.1 schwarze 40: # include <sys/endian.h>
1.32.2.3! schwarze 41: #endif
! 42:
! 43: #if defined(__linux__) || defined(__sun)
! 44: # include <db_185.h>
! 45: #else
1.1 schwarze 46: # include <db.h>
47: #endif
48:
1.2 schwarze 49: #include "mandocdb.h"
1.1 schwarze 50: #include "apropos_db.h"
51: #include "mandoc.h"
52:
1.30 kristaps 53: #define RESFREE(_x) \
54: do { \
55: free((_x)->file); \
56: free((_x)->cat); \
57: free((_x)->title); \
58: free((_x)->arch); \
59: free((_x)->desc); \
60: free((_x)->matches); \
61: } while (/*CONSTCOND*/0)
1.5 kristaps 62:
1.1 schwarze 63: struct expr {
1.5 kristaps 64: int regex; /* is regex? */
65: int index; /* index in match array */
1.6 kristaps 66: uint64_t mask; /* type-mask */
1.5 kristaps 67: int and; /* is rhs of logical AND? */
68: char *v; /* search value */
69: regex_t re; /* compiled re, if regex */
70: struct expr *next; /* next in sequence */
71: struct expr *subexpr;
1.1 schwarze 72: };
73:
74: struct type {
1.6 kristaps 75: uint64_t mask;
1.1 schwarze 76: const char *name;
77: };
78:
1.8 kristaps 79: struct rectree {
1.30 kristaps 80: struct res *node; /* record array for dir tree */
1.8 kristaps 81: int len; /* length of record array */
82: };
83:
1.1 schwarze 84: static const struct type types[] = {
1.7 kristaps 85: { TYPE_An, "An" },
86: { TYPE_Ar, "Ar" },
87: { TYPE_At, "At" },
88: { TYPE_Bsx, "Bsx" },
89: { TYPE_Bx, "Bx" },
90: { TYPE_Cd, "Cd" },
91: { TYPE_Cm, "Cm" },
92: { TYPE_Dv, "Dv" },
93: { TYPE_Dx, "Dx" },
94: { TYPE_Em, "Em" },
95: { TYPE_Er, "Er" },
96: { TYPE_Ev, "Ev" },
97: { TYPE_Fa, "Fa" },
98: { TYPE_Fl, "Fl" },
99: { TYPE_Fn, "Fn" },
100: { TYPE_Fn, "Fo" },
101: { TYPE_Ft, "Ft" },
102: { TYPE_Fx, "Fx" },
103: { TYPE_Ic, "Ic" },
104: { TYPE_In, "In" },
105: { TYPE_Lb, "Lb" },
106: { TYPE_Li, "Li" },
107: { TYPE_Lk, "Lk" },
108: { TYPE_Ms, "Ms" },
109: { TYPE_Mt, "Mt" },
110: { TYPE_Nd, "Nd" },
111: { TYPE_Nm, "Nm" },
112: { TYPE_Nx, "Nx" },
113: { TYPE_Ox, "Ox" },
114: { TYPE_Pa, "Pa" },
115: { TYPE_Rs, "Rs" },
116: { TYPE_Sh, "Sh" },
117: { TYPE_Ss, "Ss" },
118: { TYPE_St, "St" },
119: { TYPE_Sy, "Sy" },
120: { TYPE_Tn, "Tn" },
121: { TYPE_Va, "Va" },
122: { TYPE_Va, "Vt" },
123: { TYPE_Xr, "Xr" },
1.25 kristaps 124: { UINT64_MAX, "any" },
1.1 schwarze 125: { 0, NULL }
126: };
127:
128: static DB *btree_open(void);
1.17 kristaps 129: static int btree_read(const DBT *, const DBT *,
1.28 schwarze 130: const struct mchars *,
131: uint64_t *, recno_t *, char **);
1.5 kristaps 132: static int expreval(const struct expr *, int *);
1.12 schwarze 133: static void exprexec(const struct expr *,
1.30 kristaps 134: const char *, uint64_t, struct res *);
1.12 schwarze 135: static int exprmark(const struct expr *,
1.6 kristaps 136: const char *, uint64_t, int *);
1.5 kristaps 137: static struct expr *exprexpr(int, char *[], int *, int *, size_t *);
138: static struct expr *exprterm(char *, int);
1.1 schwarze 139: static DB *index_open(void);
1.11 kristaps 140: static int index_read(const DBT *, const DBT *, int,
1.30 kristaps 141: const struct mchars *, struct res *);
1.1 schwarze 142: static void norm_string(const char *,
143: const struct mchars *, char **);
144: static size_t norm_utf8(unsigned int, char[7]);
1.8 kristaps 145: static int single_search(struct rectree *, const struct opts *,
146: const struct expr *, size_t terms,
1.11 kristaps 147: struct mchars *, int);
1.1 schwarze 148:
149: /*
150: * Open the keyword mandoc-db database.
151: */
152: static DB *
153: btree_open(void)
154: {
155: BTREEINFO info;
156: DB *db;
157:
158: memset(&info, 0, sizeof(BTREEINFO));
1.29 kristaps 159: info.lorder = 4321;
1.1 schwarze 160: info.flags = R_DUP;
161:
1.2 schwarze 162: db = dbopen(MANDOC_DB, O_RDONLY, 0, DB_BTREE, &info);
1.12 schwarze 163: if (NULL != db)
1.1 schwarze 164: return(db);
165:
166: return(NULL);
167: }
168:
169: /*
170: * Read a keyword from the database and normalise it.
171: * Return 0 if the database is insane, else 1.
172: */
173: static int
1.28 schwarze 174: btree_read(const DBT *k, const DBT *v, const struct mchars *mc,
175: uint64_t *mask, recno_t *rec, char **buf)
1.1 schwarze 176: {
1.28 schwarze 177: uint64_t vbuf[2];
1.1 schwarze 178:
1.17 kristaps 179: /* Are our sizes sane? */
1.28 schwarze 180: if (k->size < 2 || sizeof(vbuf) != v->size)
1.17 kristaps 181: return(0);
1.6 kristaps 182:
1.17 kristaps 183: /* Is our string nil-terminated? */
184: if ('\0' != ((const char *)k->data)[(int)k->size - 1])
1.1 schwarze 185: return(0);
186:
1.17 kristaps 187: norm_string((const char *)k->data, mc, buf);
1.28 schwarze 188: memcpy(vbuf, v->data, v->size);
189: *mask = betoh64(vbuf[0]);
190: *rec = betoh64(vbuf[1]);
1.1 schwarze 191: return(1);
192: }
193:
194: /*
195: * Take a Unicode codepoint and produce its UTF-8 encoding.
196: * This isn't the best way to do this, but it works.
1.12 schwarze 197: * The magic numbers are from the UTF-8 packaging.
1.1 schwarze 198: * They're not as scary as they seem: read the UTF-8 spec for details.
199: */
200: static size_t
201: norm_utf8(unsigned int cp, char out[7])
202: {
1.26 kristaps 203: int rc;
1.1 schwarze 204:
205: rc = 0;
206:
207: if (cp <= 0x0000007F) {
208: rc = 1;
209: out[0] = (char)cp;
210: } else if (cp <= 0x000007FF) {
211: rc = 2;
212: out[0] = (cp >> 6 & 31) | 192;
213: out[1] = (cp & 63) | 128;
214: } else if (cp <= 0x0000FFFF) {
215: rc = 3;
216: out[0] = (cp >> 12 & 15) | 224;
217: out[1] = (cp >> 6 & 63) | 128;
218: out[2] = (cp & 63) | 128;
219: } else if (cp <= 0x001FFFFF) {
220: rc = 4;
221: out[0] = (cp >> 18 & 7) | 240;
222: out[1] = (cp >> 12 & 63) | 128;
223: out[2] = (cp >> 6 & 63) | 128;
224: out[3] = (cp & 63) | 128;
225: } else if (cp <= 0x03FFFFFF) {
226: rc = 5;
227: out[0] = (cp >> 24 & 3) | 248;
228: out[1] = (cp >> 18 & 63) | 128;
229: out[2] = (cp >> 12 & 63) | 128;
230: out[3] = (cp >> 6 & 63) | 128;
231: out[4] = (cp & 63) | 128;
232: } else if (cp <= 0x7FFFFFFF) {
233: rc = 6;
234: out[0] = (cp >> 30 & 1) | 252;
235: out[1] = (cp >> 24 & 63) | 128;
236: out[2] = (cp >> 18 & 63) | 128;
237: out[3] = (cp >> 12 & 63) | 128;
238: out[4] = (cp >> 6 & 63) | 128;
239: out[5] = (cp & 63) | 128;
240: } else
241: return(0);
242:
243: out[rc] = '\0';
1.26 kristaps 244: return((size_t)rc);
1.1 schwarze 245: }
246:
247: /*
248: * Normalise strings from the index and database.
249: * These strings are escaped as defined by mandoc_char(7) along with
250: * other goop in mandoc.h (e.g., soft hyphens).
251: * This function normalises these into a nice UTF-8 string.
252: * Returns 0 if the database is fucked.
253: */
254: static void
255: norm_string(const char *val, const struct mchars *mc, char **buf)
256: {
257: size_t sz, bsz;
258: char utfbuf[7];
259: const char *seq, *cpp;
260: int len, u, pos;
261: enum mandoc_esc esc;
1.12 schwarze 262: static const char res[] = { '\\', '\t',
1.1 schwarze 263: ASCII_NBRSP, ASCII_HYPH, '\0' };
264:
265: /* Pre-allocate by the length of the input */
266:
267: bsz = strlen(val) + 1;
268: *buf = mandoc_realloc(*buf, bsz);
269: pos = 0;
270:
271: while ('\0' != *val) {
272: /*
273: * Halt on the first escape sequence.
274: * This also halts on the end of string, in which case
275: * we just copy, fallthrough, and exit the loop.
276: */
277: if ((sz = strcspn(val, res)) > 0) {
278: memcpy(&(*buf)[pos], val, sz);
279: pos += (int)sz;
280: val += (int)sz;
281: }
282:
283: if (ASCII_HYPH == *val) {
284: (*buf)[pos++] = '-';
285: val++;
286: continue;
287: } else if ('\t' == *val || ASCII_NBRSP == *val) {
288: (*buf)[pos++] = ' ';
289: val++;
290: continue;
291: } else if ('\\' != *val)
292: break;
293:
294: /* Read past the slash. */
295:
296: val++;
297: u = 0;
298:
299: /*
300: * Parse the escape sequence and see if it's a
301: * predefined character or special character.
302: */
303:
304: esc = mandoc_escape(&val, &seq, &len);
305: if (ESCAPE_ERROR == esc)
306: break;
307:
1.12 schwarze 308: /*
1.1 schwarze 309: * XXX - this just does UTF-8, but we need to know
310: * beforehand whether we should do text substitution.
311: */
312:
313: switch (esc) {
314: case (ESCAPE_SPECIAL):
315: if (0 != (u = mchars_spec2cp(mc, seq, len)))
316: break;
317: /* FALLTHROUGH */
318: default:
319: continue;
320: }
321:
322: /*
323: * If we have a Unicode codepoint, try to convert that
324: * to a UTF-8 byte string.
325: */
326:
327: cpp = utfbuf;
328: if (0 == (sz = norm_utf8(u, utfbuf)))
329: continue;
330:
331: /* Copy the rendered glyph into the stream. */
332:
333: sz = strlen(cpp);
334: bsz += sz;
335:
336: *buf = mandoc_realloc(*buf, bsz);
337:
338: memcpy(&(*buf)[pos], cpp, sz);
339: pos += (int)sz;
340: }
341:
342: (*buf)[pos] = '\0';
343: }
344:
345: /*
346: * Open the filename-index mandoc-db database.
347: * Returns NULL if opening failed.
348: */
349: static DB *
350: index_open(void)
351: {
352: DB *db;
353:
1.2 schwarze 354: db = dbopen(MANDOC_IDX, O_RDONLY, 0, DB_RECNO, NULL);
1.1 schwarze 355: if (NULL != db)
356: return(db);
357:
358: return(NULL);
359: }
360:
361: /*
362: * Safely unpack from an index file record into the structure.
363: * Returns 1 if an entry was unpacked, 0 if the database is insane.
364: */
365: static int
1.11 kristaps 366: index_read(const DBT *key, const DBT *val, int index,
1.30 kristaps 367: const struct mchars *mc, struct res *rec)
1.1 schwarze 368: {
369: size_t left;
370: char *np, *cp;
1.24 kristaps 371: char type;
1.1 schwarze 372:
373: #define INDEX_BREAD(_dst) \
374: do { \
375: if (NULL == (np = memchr(cp, '\0', left))) \
376: return(0); \
377: norm_string(cp, mc, &(_dst)); \
378: left -= (np - cp) + 1; \
379: cp = np + 1; \
380: } while (/* CONSTCOND */ 0)
381:
1.24 kristaps 382: if (0 == (left = val->size))
383: return(0);
1.1 schwarze 384:
1.24 kristaps 385: cp = val->data;
1.27 schwarze 386: assert(sizeof(recno_t) == key->size);
1.30 kristaps 387: memcpy(&rec->rec, key->data, key->size);
388: rec->volume = index;
1.1 schwarze 389:
1.24 kristaps 390: if ('d' == (type = *cp++))
1.30 kristaps 391: rec->type = RESTYPE_MDOC;
1.24 kristaps 392: else if ('a' == type)
1.30 kristaps 393: rec->type = RESTYPE_MAN;
1.24 kristaps 394: else if ('c' == type)
1.30 kristaps 395: rec->type = RESTYPE_CAT;
1.24 kristaps 396: else
397: return(0);
398:
399: left--;
1.30 kristaps 400: INDEX_BREAD(rec->file);
401: INDEX_BREAD(rec->cat);
402: INDEX_BREAD(rec->title);
403: INDEX_BREAD(rec->arch);
404: INDEX_BREAD(rec->desc);
1.1 schwarze 405: return(1);
406: }
407:
408: /*
1.10 kristaps 409: * Search mandocdb databases in paths for expression "expr".
1.1 schwarze 410: * Filter out by "opts".
411: * Call "res" with the results, which may be zero.
1.5 kristaps 412: * Return 0 if there was a database error, else return 1.
1.1 schwarze 413: */
1.5 kristaps 414: int
1.10 kristaps 415: apropos_search(int pathsz, char **paths, const struct opts *opts,
1.12 schwarze 416: const struct expr *expr, size_t terms, void *arg,
1.30 kristaps 417: size_t *sz, struct res **resp,
1.5 kristaps 418: void (*res)(struct res *, size_t, void *))
1.1 schwarze 419: {
1.8 kristaps 420: struct rectree tree;
421: struct mchars *mc;
1.32.2.2 schwarze 422: int i;
1.8 kristaps 423:
424: memset(&tree, 0, sizeof(struct rectree));
425:
426: mc = mchars_alloc();
1.30 kristaps 427: *sz = 0;
428: *resp = NULL;
1.8 kristaps 429:
1.10 kristaps 430: /*
431: * Main loop. Change into the directory containing manpage
432: * databases. Run our expession over each database in the set.
433: */
434:
435: for (i = 0; i < pathsz; i++) {
1.32 kristaps 436: assert('/' == paths[i][0]);
1.10 kristaps 437: if (chdir(paths[i]))
1.8 kristaps 438: continue;
1.30 kristaps 439: if (single_search(&tree, opts, expr, terms, mc, i))
440: continue;
441:
442: resfree(tree.node, tree.len);
443: mchars_free(mc);
444: return(0);
1.8 kristaps 445: }
446:
1.30 kristaps 447: (*res)(tree.node, tree.len, arg);
448: *sz = tree.len;
449: *resp = tree.node;
1.8 kristaps 450: mchars_free(mc);
1.30 kristaps 451: return(1);
1.8 kristaps 452: }
453:
454: static int
455: single_search(struct rectree *tree, const struct opts *opts,
456: const struct expr *expr, size_t terms,
1.11 kristaps 457: struct mchars *mc, int vol)
1.8 kristaps 458: {
459: int root, leaf, ch;
1.1 schwarze 460: DBT key, val;
461: DB *btree, *idx;
462: char *buf;
1.30 kristaps 463: struct res *rs;
464: struct res r;
1.28 schwarze 465: uint64_t mask;
466: recno_t rec;
1.1 schwarze 467:
468: root = -1;
469: leaf = -1;
470: btree = NULL;
471: idx = NULL;
472: buf = NULL;
1.8 kristaps 473: rs = tree->node;
1.1 schwarze 474:
1.30 kristaps 475: memset(&r, 0, sizeof(struct res));
1.1 schwarze 476:
1.12 schwarze 477: if (NULL == (btree = btree_open()))
1.10 kristaps 478: return(1);
1.1 schwarze 479:
1.8 kristaps 480: if (NULL == (idx = index_open())) {
481: (*btree->close)(btree);
1.10 kristaps 482: return(1);
1.8 kristaps 483: }
1.1 schwarze 484:
485: while (0 == (ch = (*btree->seq)(btree, &key, &val, R_NEXT))) {
1.28 schwarze 486: if ( ! btree_read(&key, &val, mc, &mask, &rec, &buf))
1.1 schwarze 487: break;
488:
1.5 kristaps 489: /*
490: * See if this keyword record matches any of the
491: * expressions we have stored.
492: */
1.28 schwarze 493: if ( ! exprmark(expr, buf, mask, NULL))
1.1 schwarze 494: continue;
495:
496: /*
497: * O(log n) scan for prior records. Since a record
498: * number is unbounded, this has decent performance over
499: * a complex hash function.
500: */
501:
502: for (leaf = root; leaf >= 0; )
1.30 kristaps 503: if (rec > rs[leaf].rec &&
1.5 kristaps 504: rs[leaf].rhs >= 0)
505: leaf = rs[leaf].rhs;
1.30 kristaps 506: else if (rec < rs[leaf].rec &&
1.5 kristaps 507: rs[leaf].lhs >= 0)
508: leaf = rs[leaf].lhs;
1.12 schwarze 509: else
1.1 schwarze 510: break;
511:
1.5 kristaps 512: /*
513: * If we find a record, see if it has already evaluated
514: * to true. If it has, great, just keep going. If not,
515: * try to evaluate it now and continue anyway.
516: */
517:
1.30 kristaps 518: if (leaf >= 0 && rs[leaf].rec == rec) {
1.5 kristaps 519: if (0 == rs[leaf].matched)
1.28 schwarze 520: exprexec(expr, buf, mask, &rs[leaf]);
1.1 schwarze 521: continue;
1.5 kristaps 522: }
1.1 schwarze 523:
524: /*
1.5 kristaps 525: * We have a new file to examine.
526: * Extract the manpage's metadata from the index
527: * database, then begin partial evaluation.
1.1 schwarze 528: */
529:
1.28 schwarze 530: key.data = &rec;
1.1 schwarze 531: key.size = sizeof(recno_t);
532:
533: if (0 != (*idx->get)(idx, &key, &val, 0))
534: break;
535:
1.5 kristaps 536: r.lhs = r.rhs = -1;
1.11 kristaps 537: if ( ! index_read(&key, &val, vol, mc, &r))
1.1 schwarze 538: break;
539:
1.5 kristaps 540: /* XXX: this should be elsewhere, I guess? */
541:
1.30 kristaps 542: if (opts->cat && strcasecmp(opts->cat, r.cat))
1.1 schwarze 543: continue;
1.22 kristaps 544:
1.30 kristaps 545: if (opts->arch && *r.arch)
546: if (strcasecmp(opts->arch, r.arch))
1.22 kristaps 547: continue;
1.1 schwarze 548:
1.8 kristaps 549: tree->node = rs = mandoc_realloc
1.30 kristaps 550: (rs, (tree->len + 1) * sizeof(struct res));
1.1 schwarze 551:
1.30 kristaps 552: memcpy(&rs[tree->len], &r, sizeof(struct res));
553: memset(&r, 0, sizeof(struct res));
1.12 schwarze 554: rs[tree->len].matches =
1.8 kristaps 555: mandoc_calloc(terms, sizeof(int));
1.1 schwarze 556:
1.28 schwarze 557: exprexec(expr, buf, mask, &rs[tree->len]);
1.12 schwarze 558:
1.1 schwarze 559: /* Append to our tree. */
560:
561: if (leaf >= 0) {
1.30 kristaps 562: if (rec > rs[leaf].rec)
1.8 kristaps 563: rs[leaf].rhs = tree->len;
1.1 schwarze 564: else
1.8 kristaps 565: rs[leaf].lhs = tree->len;
1.1 schwarze 566: } else
1.8 kristaps 567: root = tree->len;
1.12 schwarze 568:
1.8 kristaps 569: tree->len++;
1.1 schwarze 570: }
1.12 schwarze 571:
1.8 kristaps 572: (*btree->close)(btree);
573: (*idx->close)(idx);
1.1 schwarze 574:
575: free(buf);
1.30 kristaps 576: RESFREE(&r);
1.8 kristaps 577: return(1 == ch);
1.5 kristaps 578: }
579:
1.30 kristaps 580: void
581: resfree(struct res *rec, size_t sz)
1.5 kristaps 582: {
1.30 kristaps 583: size_t i;
1.5 kristaps 584:
1.30 kristaps 585: for (i = 0; i < sz; i++)
586: RESFREE(&rec[i]);
587: free(rec);
1.1 schwarze 588: }
589:
1.13 kristaps 590: /*
591: * Compile a list of straight-up terms.
592: * The arguments are re-written into ~[[:<:]]term[[:>:]], or "term"
593: * surrounded by word boundaries, then pumped through exprterm().
594: * Terms are case-insensitive.
595: * This emulates whatis(1) behaviour.
596: */
597: struct expr *
598: termcomp(int argc, char *argv[], size_t *tt)
599: {
600: char *buf;
601: int pos;
602: struct expr *e, *next;
603: size_t sz;
604:
605: buf = NULL;
606: e = NULL;
607: *tt = 0;
608:
1.15 schwarze 609: for (pos = argc - 1; pos >= 0; pos--) {
610: sz = strlen(argv[pos]) + 18;
1.13 kristaps 611: buf = mandoc_realloc(buf, sz);
1.15 schwarze 612: strlcpy(buf, "Nm~[[:<:]]", sz);
1.13 kristaps 613: strlcat(buf, argv[pos], sz);
614: strlcat(buf, "[[:>:]]", sz);
615: if (NULL == (next = exprterm(buf, 0))) {
616: free(buf);
617: exprfree(e);
618: return(NULL);
619: }
1.15 schwarze 620: next->next = e;
1.13 kristaps 621: e = next;
622: (*tt)++;
623: }
624:
625: free(buf);
626: return(e);
627: }
628:
629: /*
630: * Compile a sequence of logical expressions.
631: * See apropos.1 for a grammar of this sequence.
632: */
1.1 schwarze 633: struct expr *
1.5 kristaps 634: exprcomp(int argc, char *argv[], size_t *tt)
1.1 schwarze 635: {
1.5 kristaps 636: int pos, lvl;
637: struct expr *e;
638:
639: pos = lvl = 0;
640: *tt = 0;
641:
642: e = exprexpr(argc, argv, &pos, &lvl, tt);
643:
644: if (0 == lvl && pos >= argc)
645: return(e);
646:
647: exprfree(e);
648: return(NULL);
649: }
650:
651: /*
652: * Compile an array of tokens into an expression.
653: * An informal expression grammar is defined in apropos(1).
654: * Return NULL if we fail doing so. All memory will be cleaned up.
655: * Return the root of the expression sequence if alright.
656: */
657: static struct expr *
1.9 kristaps 658: exprexpr(int argc, char *argv[], int *pos, int *lvl, size_t *tt)
1.5 kristaps 659: {
660: struct expr *e, *first, *next;
661: int log;
662:
663: first = next = NULL;
664:
665: for ( ; *pos < argc; (*pos)++) {
666: e = next;
667:
668: /*
669: * Close out a subexpression.
670: */
671:
672: if (NULL != e && 0 == strcmp(")", argv[*pos])) {
673: if (--(*lvl) < 0)
674: goto err;
675: break;
676: }
677:
678: /*
679: * Small note: if we're just starting, don't let "-a"
680: * and "-o" be considered logical operators: they're
681: * just tokens unless pairwise joining, in which case we
682: * record their existence (or assume "OR").
683: */
684: log = 0;
685:
686: if (NULL != e && 0 == strcmp("-a", argv[*pos]))
1.12 schwarze 687: log = 1;
1.5 kristaps 688: else if (NULL != e && 0 == strcmp("-o", argv[*pos]))
689: log = 2;
690:
691: if (log > 0 && ++(*pos) >= argc)
692: goto err;
693:
694: /*
695: * Now we parse the term part. This can begin with
696: * "-i", in which case the expression is case
697: * insensitive.
698: */
699:
700: if (0 == strcmp("(", argv[*pos])) {
701: ++(*pos);
702: ++(*lvl);
703: next = mandoc_calloc(1, sizeof(struct expr));
704: next->subexpr = exprexpr(argc, argv, pos, lvl, tt);
705: if (NULL == next->subexpr) {
706: free(next);
707: next = NULL;
708: }
709: } else if (0 == strcmp("-i", argv[*pos])) {
710: if (++(*pos) >= argc)
711: goto err;
712: next = exprterm(argv[*pos], 0);
713: } else
714: next = exprterm(argv[*pos], 1);
715:
716: if (NULL == next)
717: goto err;
718:
719: next->and = log == 1;
720: next->index = (int)(*tt)++;
721:
722: /* Append to our chain of expressions. */
723:
724: if (NULL == first) {
725: assert(NULL == e);
726: first = next;
727: } else {
728: assert(NULL != e);
729: e->next = next;
730: }
731: }
732:
733: return(first);
734: err:
735: exprfree(first);
736: return(NULL);
737: }
738:
739: /*
740: * Parse a terminal expression with the grammar as defined in
741: * apropos(1).
742: * Return NULL if we fail the parse.
743: */
744: static struct expr *
745: exprterm(char *buf, int cs)
746: {
747: struct expr e;
1.1 schwarze 748: struct expr *p;
1.3 schwarze 749: char *key;
1.5 kristaps 750: int i;
751:
752: memset(&e, 0, sizeof(struct expr));
1.1 schwarze 753:
1.5 kristaps 754: /* Choose regex or substring match. */
1.3 schwarze 755:
1.4 kristaps 756: if (NULL == (e.v = strpbrk(buf, "=~"))) {
1.3 schwarze 757: e.regex = 0;
1.4 kristaps 758: e.v = buf;
1.3 schwarze 759: } else {
760: e.regex = '~' == *e.v;
761: *e.v++ = '\0';
762: }
1.1 schwarze 763:
1.5 kristaps 764: /* Determine the record types to search for. */
1.3 schwarze 765:
766: e.mask = 0;
1.4 kristaps 767: if (buf < e.v) {
768: while (NULL != (key = strsep(&buf, ","))) {
1.3 schwarze 769: i = 0;
770: while (types[i].mask &&
1.4 kristaps 771: strcmp(types[i].name, key))
1.3 schwarze 772: i++;
773: e.mask |= types[i].mask;
774: }
775: }
776: if (0 == e.mask)
777: e.mask = TYPE_Nm | TYPE_Nd;
1.1 schwarze 778:
1.5 kristaps 779: if (e.regex) {
1.13 kristaps 780: i = REG_EXTENDED | REG_NOSUB | (cs ? 0 : REG_ICASE);
1.5 kristaps 781: if (regcomp(&e.re, e.v, i))
782: return(NULL);
783: }
1.1 schwarze 784:
1.3 schwarze 785: e.v = mandoc_strdup(e.v);
1.1 schwarze 786:
787: p = mandoc_calloc(1, sizeof(struct expr));
788: memcpy(p, &e, sizeof(struct expr));
789: return(p);
790: }
791:
792: void
793: exprfree(struct expr *p)
794: {
1.5 kristaps 795: struct expr *pp;
1.12 schwarze 796:
1.5 kristaps 797: while (NULL != p) {
798: if (p->subexpr)
799: exprfree(p->subexpr);
800: if (p->regex)
801: regfree(&p->re);
802: free(p->v);
803: pp = p->next;
804: free(p);
805: p = pp;
806: }
807: }
1.1 schwarze 808:
1.5 kristaps 809: static int
1.12 schwarze 810: exprmark(const struct expr *p, const char *cp,
1.6 kristaps 811: uint64_t mask, int *ms)
1.5 kristaps 812: {
813:
814: for ( ; p; p = p->next) {
815: if (p->subexpr) {
816: if (exprmark(p->subexpr, cp, mask, ms))
817: return(1);
818: continue;
819: } else if ( ! (mask & p->mask))
820: continue;
1.1 schwarze 821:
1.5 kristaps 822: if (p->regex) {
823: if (regexec(&p->re, cp, 0, NULL, 0))
824: continue;
1.16 kristaps 825: } else if (NULL == strcasestr(cp, p->v))
826: continue;
1.5 kristaps 827:
828: if (NULL == ms)
829: return(1);
830: else
831: ms[p->index] = 1;
832: }
1.1 schwarze 833:
1.5 kristaps 834: return(0);
1.1 schwarze 835: }
836:
837: static int
1.5 kristaps 838: expreval(const struct expr *p, int *ms)
1.1 schwarze 839: {
1.5 kristaps 840: int match;
1.1 schwarze 841:
1.5 kristaps 842: /*
843: * AND has precedence over OR. Analysis is left-right, though
844: * it doesn't matter because there are no side-effects.
845: * Thus, step through pairwise ANDs and accumulate their Boolean
846: * evaluation. If we encounter a single true AND collection or
847: * standalone term, the whole expression is true (by definition
848: * of OR).
849: */
850:
851: for (match = 0; p && ! match; p = p->next) {
852: /* Evaluate a subexpression, if applicable. */
853: if (p->subexpr && ! ms[p->index])
854: ms[p->index] = expreval(p->subexpr, ms);
855:
856: match = ms[p->index];
857: for ( ; p->next && p->next->and; p = p->next) {
858: /* Evaluate a subexpression, if applicable. */
859: if (p->next->subexpr && ! ms[p->next->index])
1.12 schwarze 860: ms[p->next->index] =
1.5 kristaps 861: expreval(p->next->subexpr, ms);
862: match = match && ms[p->next->index];
863: }
864: }
865:
866: return(match);
867: }
868:
869: /*
870: * First, update the array of terms for which this expression evaluates
871: * to true.
872: * Second, logically evaluate all terms over the updated array of truth
873: * values.
874: * If this evaluates to true, mark the expression as satisfied.
875: */
876: static void
1.12 schwarze 877: exprexec(const struct expr *e, const char *cp,
1.30 kristaps 878: uint64_t mask, struct res *r)
1.5 kristaps 879: {
1.1 schwarze 880:
1.5 kristaps 881: assert(0 == r->matched);
1.12 schwarze 882: exprmark(e, cp, mask, r->matches);
883: r->matched = expreval(e, r->matches);
1.1 schwarze 884: }
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